Friction shock-absorbing mechanism



May 21, 1929.- K

, w. A. Gx-:lER 1,713,960 FR'ICTION SHOCK ABSORBING MCHANISM Filed April22, 1927 CII Patented May 2l, 1929.

1,713,96ti`- UNITED ,STATESl P AriiNrv OFFICE.

WILLIAM AQGEIGER, or CHICAGO, ILLINOIS, AssIGivon rro W.

n. Minna, iiro., or

CHICAGO, iLLINoIsAconronA'rioN or DELAWARE.

FRICTION 'SHOCK-Ansonisine MEcHANisM;

Application led April 22, 1927. Serial No. 185,736.

including a column element having friction surfaces thereon, and springresisted friction means co-opeiating with the column elcinent, includinga combined pressure trans-l mitting spreading element, wherein simpleand efficient readily applied means is provided for anchoring thecombined pressure transmitting and spreading element to the columnelement, thereby limiting outward movement of the former and maintainingthe parts of the mechanism assembled.

In the drawings, forming a part of this specification, Figure 1is ahorizontal longitudinal sectional View of a portion of a railway draftArigging vsho Ying my improvements in connection therewith. lFigure 2 isa front -end elevational view of the shockl absorbing mechanism properand Figure 3 is a longitudinal vertical sectional view of the front endportion ofthe shock absorbing mechanism corresponding substantially tothe line 3 3 of Figure 1. Infsaid drawings, 1 0-10 indicatechannel-shaped lcenter or draft sills of a railway draft rigging, havingthe usualfroiit stop plugs 11-11 and the usual rear stop 'lugs 1 2-12securedl to the inner sides thereof. The-inner end of the drawbar isdesignated by 13 to which is op' eratively connected a yoke 14. rl`heshock absorbing mechanism proper and a front main follower 15 aredisposed within the yoke. The yoke and the parts tlierewi'thinaresupported inoperative vpositionby a detachable' saddle plate lfixedtothedraftsills. 1-

`Myimproved shock absorbing mechanism proper comprises broadly: Acombined friction Shellands rinfr'caOe Al a wedOc block p o c 7 i:

B; two friction shoes C aud'D; a main' spaced top and bottom walls-18-18 and aY transverse rear end :wall A19.` :The end wall 19, as mostclearly shown in` Figures 1 and 2,

is extendedlaterally beyond'the side walls 17 and cofoperates with thestop lugs 12 in the `manner of the usual rear follower.y `The casting Ais preferably reinforced by longitudinally extending ribs which areformed integral with-the side walls 17 and the end wall 19. .At theforward end'ofthe coni-` bined spring-cage and friction shell A, theside walls are thickened as indicated atr20 and tliefthickenedportions'20 are grooved as indicated at 21 and 22 to receive ribs orextensions on liners 23, therebyanchoring.A

the liners to the cage A. They liners 23, as shown, are two in numberand present longitudinally disposed interior V-shaped friction surfaces24: onthe inner sides thereof. 'lhe friction. surfaces 24 arepreferably'converged inwardly of the mechanism asinost clearly shown inFigure 1. The liners 23, together with the top and bottom walls 18 atthe forward end of the `spring cage A, define the. friction shellsection of the ly shown in Figures 1 and v2, the' liners 23V have curvedbearing faces' engaging the walls ofthe cage A and protrude inwardlybeyond said'side walls, thereby presenting trans; verse abutment faces'at the rear ends` thereof adapted to co-operate with the spring fol.Alower F to limit outward movementoffthe same. a y Y The wedge block Bliasa flat front lend face bearing directly yonfthe inner side of themain follower 15. -At the K' inner end, the wedge block B is providedwith a pair of inwardly converging Vshaped wedge' faces 25 and'25 on theopposite' sides tl'iereof, the wedge face 25 being preferably 'disposedyrespect to the longitudinal axis of the mechanism and the wedgeface26being prefer.-V

ably disposed ata relativelyblunt releasing angle with respect tosaid'axis. 'The wedge block B visfprovided with averticalxbore 27adjacentthe inner end thereof adapted to receivey the retaining pinsH-H. The block B is also'provided with a longitudinal. central bore'28intersecting the vertical bore 27. The bore'28is enlarged :at its outerend as indicated at 29 and'opens through the front end'of the wedgeblock B. At the juncture of Vthe bore 28 with the :enlarged portion29,*the'same is threaded as indicated at 30. A plug 31 is disposedwithin the inner end of the bore 28 to maintain'the retaining pins Hseparated with their outery same. As clear,- v

`at a relatively keen'wedgea'cting angle with Cil ends projecting asmost clearly shown in Figure 3. The plug 31 has a conical inner end 32and a threaded head 33 co-operating with the threaded portion of thebore 28.

At the outer end, the plug is provided with` a square wrench receivingboss 34 by which the same be sciewed into the threaded portion of theopening 28. It will be evident that when the plug 3l is inserted withinthe wedge, the conical end 32 thereof engages the inner ends of the pinsH, thereby spreading the same apart and projecting the outer ends beyondthe top and bottom faces of the wedge block B. lhen the plug 3l is fullyinserted as shown in Figure 3, the shank portion thereof maintains thepins projected. The top and bottom ends of the pins I-I work inlongitudinal slots 35 provided in the top and bottom walls of the springcage A. The slots 35 as shown in Figure 3 terminate short of the outerend of the cage A, thereby presenting shoulders co-operating with thevprojecting portions of the pins II to limit outward movement of thewedge B and maintain the same assembled with the cage A.

The friction shoes C and Dare interposed between the wedge block B andthe liners 23. The shoes C and D are of similar design except asVhereinafter pointed out. Each of the shoes is provided with alongitudinally disposed outer V-shaped friction surface 36 adapted toengage the friction surfaces 24 of the corresponding liner23. On theinner side, each shoe is provided with a'lateral enlargement 37 having aV-shaped wedge face on the front side thereof.A The wedge face of theshoe C is designated by 38 and co-operates with the wedge face 25 of theblock B and is correspondingly inclined thereto and the wedge face ofthe shoe D is designated by 39 and co-operates withV the wedge face 26of the block B and is correspondingly inclined thereto.

The spring resistance E which is disposed within the spring cage Acomprises a rela-V tively light inner coil and a heavierouter coil. Theouter coil of the spring resistance has the front end thereof bearing onthe spring follower F. The spring follower F is the form of a flangedring havingtlie laterally projecting flange section Il() thereofengaging behind the liners 23, tlieieby limiting outward `movement ofthe spring follower. The central coil of the spring E extends throughthe ring like spring follower F and has the forward end thereof bearingonk the auxiliaryspring follower G, which is in the form of a diskinterposed between saidk spring and the inner ends of the enlargementson the friction shoes C and D. The parts are so proportioned th at whenthe mechanism is assembled, the spring resistance E is preferably underinitial compression. Inasmuch as the inner coil of theV springresistance which Aasheretofore stated,

is under initial compression, directly co-opcrates with the frictionshoes, the same tends to force the shoes outwardly, thereby compensatingfor wear of the various friction and wedge faces of the mechanism.

In assembling the mechanism, the spring resistance element E, the liners23, the spring follower F and the auxiliary spring follower Gr areinserted within the combined spring cage and friction shell. The wedgeblock, with the pins II disposed within the bore 27, is then insertedwithin the front end of the combined spring cage and friction shell,with the outer ends of the pins being disposed inwardly of or inalignment with the top and bottom faces of the wedge block so as toclear the top and bottom walls of the cage A. lhen the wedge block hasbeen inserted, the proper distance, so that the ends of the pins II willengage within the slots 35 of the top and bottoni walls of the cage A,when projected, the plug 3l is inserted through the front end of thewedge and screwed home. Due to the taper of the inner end of the plug asliereiiibefore pointed out', the pins II will be forced apart and whenthe, plug has been screwed home, the shank of the plug will maintain thepins in the projected position shown in Figure 8.l

Although I have herein showna screw threaded plug for holding the pinsprojected.` it will be evident that a plug may be employed which has adriving fit with the wedge block. It will also bev evident that anyother suitable means may be employed for holding the plug in positionwithin the wedge.

The operation of my improved shock absorbing mechanism, assuming acompression stroke, is as follows: The main follower 15 and the combinedspring cage and friction shell A will be moved relatively toward eachother, thereby forcing the wedge block in wardly of the cage and placingthe shoes under lateralV pressure while carrying the same 'inwardly onthe friction surfaces of the liners. The described action will continueeither until the actuating force is reduced or the follower l5 engagesthe outer end of the combined spring cage andV friction shell, whereuponthe actuating force will be transmitted directly through the cage, thelatter acting as a solid column load transmitting member, preventing thesprings from being unduly compressed. In release, when the actuatingforce is reduced, the expansive action of the main spring resistance Ewill re turn all of the parts to normal position, outwaid movement ofthe wedge block B being limited by the pins H engaging the front endwalls of the slots 35 of the cage A. Inasmueh as the block B is inwedging engagement -with the friction shoes, the outward movement of theshoes will beliinited while movement ofthe wedge block is arrested.

While I have herein shown and described what I now consider thepreferred manner Vof carrying out my invention, the same is i the wedgeblock in the path of the stop shoulder of the shell to limit outwardmoveinent of the wdege block and hold the parts assembled, saidretaining element being displaceable to house the same entirely withinthe wedge block when the block is being assembled with the shell, andbeing movable t0 lprojected position after the wedge has been insertedwithin the shell; kmeans for holding said element projected; and springmeans within the cage opposing movement of the shoes inwardly. l

2. In a friction shock absorbing mechanism, the combination with africtiony shell, said shell having stop shoulders thereon; of frictionshoes co-operating with the shell; a wedge block engaging the shoes; a`pair of Y Y displaceable retaining pins mounted on the wedge, said pinsbeing movable to project the outer end portions thereof beyond thewedge; means carried by the wedge, interposed between the inner ends ofthe pins for holding said pins projected outwardly of the wedge in thepath of said shoulders to maintain the wedge assembled with the shell;

and spring `means within the shell opposing movement of the shoes.

3. In a friction shock absorbing mechanism, the combination with `arectangular friction shell having interior friction sur-v faces on twoopposite walls thereof, the revmaining walls of the shellbeing providedVwith slots; of a pair of friction shoes cooperating with the shellfriction surfaces; a'

pressure transmitting block having wedging engagement with the shoes;transversely disposed retainer pins mounted in said block; a plugengaging between the inner ends of said pins for holding the sameprojected beyond the opposite sides of the block with the outer-'endsthereof in the slots of the shell to anchor the `wedge to the shell;said plug having a tapered point, whereby when theV plug is forced intothe wedge betweenthe pins, the pins are projected outwardly into saidslots; and spring means within the shell resisting inward movement ofthe shoes.

In witness that I claim the foregoing I have hereunto subscribed my namethis 18th day of April, 1927.

WILLIAM A. GEIGER

